The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 30, 2002
Filed:
Mar. 07, 2000
Kobe Steel, Ltd., Kobe, JP;
Abstract
A hydraulic control apparatus for a working machine in which a flow rate and a direction of pressure oil discharged from a hydraulic pump are controlled by a control valve to supply it to a swing motor, comprising: a bleed-off oil path for bleeding off a part of the pressure oil supplied to the swing motor, a cut valve provided on the bleed-off oil path to adjust a bleed-off amount, a controller for controlling the cut valve through a solenoid proportional valve, and pressure sensors for detecting an operating amount of a remote control valve for swing, characterized in that the controller sets the bleed-off amount according to the operating amount detected by the pressure sensors, controls an opening area of the cut valve on the basis of the bleed-off amount set, and suppresses the shock when sudden swinging operation takes place.